Intestinal malrotation is a developmental defect in a fetus’s intestinal tract. It occurs in roughly 1 in every 500 live births. While more boys show symptoms in the first month of life, both boys and girls are affected equally.
The problem arises at approximately the tenth week of gestation. Normally at this time, the intestine that has been developing outside the body near the base of the umbilical cord moves into the abdominal cavity. As it moves into the abdomen it makes two rotations and is then fixed into its normal permanent position – the small bowel in the middle of the abdomen and the colon (large intestine) flanking it on both sides and across the top. This normal positioning doesn’t happen with malrotation.
With malrotation, the entire colon is positioned on the left side of the abdomen while the small intestine is on the right. The cecum (beginning of the colon) and appendix are unattached or may be incorrectly attached by bands to the duodenum (beginning of the small intestine) which can cause a blockage. Since the intestines are not properly anchored, they may twist and cut off their own blood supply, a condition known as volvulus. This is serious and can end in the loss of most of the intestine or even death.
Malrotation of the intestine usually is not evident until the intestine becomes twisted or blocked and symptoms occur. In some patients twisting and blockage do not happen and symptoms never occur, while in other patients symptoms can manifest themselves at any time. Symptoms can include greenish-yellow vomit (from bile, a digestive fluid), abdominal pain, abdominal swelling, rapid heart rate, shock, rapid breathing, or blood in a bowel movement. If you should ever see these symptoms in an infant, call the healthcare provider immediately as he will want to examine the baby. Various blood tests and diagnostic imaging (x-rays, ultrasound, etc.) may be taken to check for blockages or twisting. If they are found, surgery to correct the situation will be performed. If the blood supply to the region is compromised, it may be necessary to perform follow-up surgery to remove any permanently damaged intestine.
There usually are no long-term problems when surgery occurs before permanent damage to the intestine sets in. If large portions of damaged intestine are removed, long-term digestive problems such as the ability to absorb nutrients and liquids can be severely compromised. Nutrition may need to be obtained through long-term IV solutions.
The March of Dimes has funded nearly one million dollars in research involving intestinal malrotation and the mechanism of intestinal coiling. Hopefully, one day we will discover what causes the development to go awry and how it can be prevented in the future.